It is often necessary or desirable to selectively control the output or operating rate of numerous kinds of electronic loads. Typically, the voltage and/or current applied to the load is/are varied in order to achieve the control effect. One type of load that can be controlled is an organic light emitting diode (OLED). By selectively varying the average applied electrical current, the luminance (i.e., brightness) of an OLED can be suitably modulated.